Plastics, such as thermoplastic polymers or thermoset polymers, may be used in a number of different commercial products. Industries employing polymers include the printing industry, the paint industry, the fabric industry, and the plastic industry. In a number of these products and industries, the color of the polymer product may be important.
Currently, most, if not all, precise measurements of object color are made by one of two devices: a tristimulus colorimeter or a reflectance spectrophotometer. These devices suffer from a number of disadvantages. These devices usually require flat object samples and precisely controlled viewing conditions in order to provide a satisfactory measurement of object color. This is particularly disadvantageous for the typical polymer product manufacturing environment. Furthermore, none of these devices provide spatial resolution of the color measurements, that is the ability to obtain color measurements for multiple locations on the surface of the object or sample. In fact, these devices often render a single measurement of the "average" color of the sample within the field of view of the instrument or device. In addition, these devices tend to be expensive due to the manufacturing care necessary to construct a device capable of providing precise color measurements suitable for laboratory use.
Video cameras may be used to measure the color of objects, such as polymer samples, as well. However, these also suffer from disadvantages, such as the lack of precision of the color measurements obtained, the restriction that the object being measured be a flat sample, and the possibility of the need for human intervention during the measurement process to correct for significant errors that may arise from such an approach. Therefore, a need exists for an automated, nondestructive, noninvasive, economical and relatively time-efficient method or device that allows for the precise measurement of color in a manufacturing environment so that real-time information regarding sample color, such as a sample from a compounded polymer mixture, may be obtained.